A multiplicity of different sensor systems for sensing the surroundings has already been disclosed in the prior art. It is also already known to obtain and transmit information about the vehicle surroundings via telematics systems which communicate in a wireless fashion. Under certain conditions and when these systems are sufficiently reliable, the acquired information can be used for interventions in the vehicle control, for example in the form of an autonomous emergency braking operation.
In this context, WO 2004/085220 discloses, for example, an electronic control system for a vehicle and a method for determining an intervention in a vehicle system, independently of the driver. In this context, a driver's request module firstly determines a driver's request from the brake pedal travel, from transfer movements between the pedals and from the brake pressure in the brake system. A hazard computer subsequently determines the hazard potential which is present, by evaluating the driver's request and evaluating further data such as surroundings sensor data. Furthermore, the electronic control system is also connected to various autonomously operating assistance systems. The driver's request data and the surroundings data are evaluated by the hazard computer and corresponding request commands are output to the individual assistance systems. The request commands relate here both to passive and to active safety. A vehicle control intervention can therefore be carried out as a function of the detected hazard potential.
WO 2009/071345 A1 describes a central control unit for a plurality of assistance systems which are provided in a motor vehicle, at least one assistance system of which is equipped with surroundings sensors. The central control unit connects the individual assistance systems and logically combines the sensor information items obtained from the assistance systems with one another in order to subject non-redundant sensor information items to analytical checking and plausibility testing. In addition, it is possible, for example in the case of a camera, to check the sensor information by comparing it with sensor information from the same sensor which has been acquired later. If the camera captures the same object over a specific time frame, or over a plurality of measurement cycles, the validity of the existence of said object can be considered to have been checked. Furthermore, there is a description of the possibility of using a surroundings sensor to check the validity of an information item received via vehicle-to-X communication or of receiving an information item whose plausibility has already been tested by means of an extraneous transmitter.
The non-published document DE 10 2010 031 466 A1 describes a method for checking the validity of information which has been acquired by means of vehicle-to-X communication, without involving a surroundings sensor for checking the validity of the received information. For this purpose, the position information of the transmitter, contained in the vehicle-to-X information item, is compared with position information of the transmitter which is calculated by the receiver itself when the message is received. In order to be able to calculate the position of the transmitter, a transmitter validity-checking device with at least two antennas is also described, said antennas having a different geometry or a different material composition or at least being arranged at different mounting locations on the vehicle. By comparing the field strengths received in the individual antennas it is possible to draw a conclusion about the actual position of the transmitter and therefore to check the validity thereof, if appropriate. However, if the calculated position deviates from the position transmitted by means of vehicle-to-X communication, the entire content of the received vehicle-to-X information is rejected as unreliable.
A disadvantage of the methods according to the prior art is that a safety-relevant vehicle-to-X information item cannot be used for intervention into the vehicle control in order to avoid an accident until said information item has previously been subjected to a comparatively lengthy validity-checking process. According to the prior art, the validity checking can be performed by means of surroundings sensors or by means of a comparison of the received field strengths. If the validity of the received vehicle-to-X information item is checked by means of position determination of the transmitter on the basis of the received field strengths, it is necessary firstly to receive a series of vehicle-to-X information items from the same transmitter before the position of said transmitter can be determined with adequate precision. As a result, a time period which is, under certain circumstances, critical passes unused before an autonomous intervention in order to avoid an accident can be made in the vehicle control. Likewise, reliable detection of a situation by means of a surroundings sensor generally requires a plurality of measurement cycles and processing cycles before the surroundings sensor data is available for the validity checking of the vehicle-to-X information. As a result, a time period which is, under certain circumstances, critical for avoiding an accident also passes here without being used. Since the validity of a vehicle-to-X information item is checked by means of surroundings sensors in most application cases, there is therefore a particular requirement for a method for rapid object detection by means of surroundings sensors.
The invention is therefore based on the object of proposing a method and a system which permit accelerated object detection and/or accelerated object attribute detection by means of a surroundings sensor.
This object is achieved according to the invention by means of the method for accelerated object detection and/or for accelerated object attribute detection according to this invention, and the system for accelerated object detection and/or for accelerated object attribute detection.
According to the inventive method for accelerated object detection and/or for accelerated object attribute detection, a first information item is acquired by a vehicle-to-X communication device, wherein the first information item describes at least one object and/or at least one object attribute in an evaluated data form, and a second information item is acquired by at least one individual sensor or by a sensor group, wherein the second information item describes the at least one object and/or the at least one object attribute in sensor raw data form. An object detection algorithm and/or an object attribute detection algorithm is applied to sensor raw data of the second information item. The method according to the invention is defined by the fact that a threshold value of the object attribute detection algorithm and/or of the object detection algorithm for detecting the at least one object and/or at least one object attribute described by the first information item is reduced in the sensor raw data of the second information item.
The term sensor raw data is understood within the scope of the invention to mean all unevaluated signals which are output by different surroundings sensors for evaluation. On the other hand, the term evaluated data form within the scope of the invention refers to the already evaluated sensor raw data of the different surroundings sensors and to the data form of all the information items transmitted by means of vehicle-to-X communication. In an evaluated data form, objects and object attributes are described in such a way that they can be processed immediately by driver assistance systems and other vehicle devices without further data format conversion or evaluation processes.
The method therefore provides the advantage that the validity of a first information item which has been acquired by means of a vehicle-to-X communication device can be comparatively quickly checked by means of an individual sensor or a sensor group, since the object detection or object attribute detection is carried out comparatively quickly by the individual sensor or the sensor group on the basis of the reduced threshold values. The information whose validity has been checked can be made available to various, even autonomously operating driver assistance systems, on the basis of the high level of reliability of said information. The driver assistance systems can in turn use the information whose validity has been checked for, for example, intervention in the vehicle control in order to avoid an accident. Likewise, information can, however, also be used as a reliable basis for outputting a warning to the driver.
There is preferably provision that the object detection algorithm detects the existence of an object and/or the object attribute detection algorithm detects a direction of movement and/or a relative and/or absolute position and/or a speed and/or a type of the object. This provides the advantage that an object is firstly detected as existing by means of the object detection algorithm. This is a fundamental information item for the assessment of a situation which is present and for possible reactions of different driver assistance systems. The position of a detected object is also of equal importance for the assessment of a situation which is present. This is the only way in which it is possible to assess whether or not a detected object constitutes a potential hazard. If the direction of movement and the speed of the object are additionally known by virtue of the object attribute detection algorithm, the assessment of the situation can be improved to the effect that a possible hazard can be assessed even more precisely by means of comparison with the vehicle's own direction of movement and speed. Finally, the type of the object is also significant since, for example, a collision with a vehicle parked at the edge of the road is preferred to a collision with a pedestrian.
In a further preferred embodiment, there is provision that the threshold value is reduced in terms of the number of measurement cycles which are necessary to reach said value, during which number of measurement cycles the second information item is acquired. This speeds up the object detection or the object attribute detection since each measurement cycle is assigned a fixed computational time. Reducing the measurement cycles therefore reduces the necessary computational time up to the conclusion of the object attribute detection or the conclusion of the object attribute detection.
There is expediently provision that the threshold value is reduced in terms of the statistical probability, necessary to reach said value, of the at least one object and/or the at least one object attribute being detected in the sensor raw data. This likewise permits accelerated object detection or object attribute detection, which, in combination with the reduction in the number of measurement cycles necessary to reach the threshold value, brings about additional acceleration. Reducing the threshold value in terms of the statistical probability which is necessary to reach it provides the advantage that an object can be more quickly detected in the sensor raw data. It is therefore possible, for example, for an object or object attribute which is described by the first information item to serve as a target specification for the object detection or object attribute detection in the sensor raw data of the second information item. If the object or object attribute which is described by the first information item can be detected, in terms of its detection probability, only as one of a plurality of possible objects or object attributes in the sensor raw data, substantially reliable detection can be performed by virtue of the correspondingly reduced threshold values for the detection of the object or object attribute described by the first information item, even in the case of a comparatively low detection probability.
Furthermore it is advantageous that the at least one object and/or the at least one object attribute is detected in the sensor raw data of the second information item as soon as the threshold value of the object detection algorithm and/or of the object attribute detection algorithm is reached. This firstly provides the advantage that, as before, a threshold has to be reached at which the certainty is high enough to reliably detect an object or object attribute in the sensor raw data. The fact that the object or object attribute is detected when the threshold value is reached also provides the advantage that a reliable information item, which can be used, for example, to check the validity of further information items, is now available.
According to a further preferred embodiment of the invention there is provision that when the threshold value is reached, a description of the at least one detected object and/or of the at least one detected object attribute of sensor raw data form is converted into an evaluated data form. As a result, the information items which are detected with certainty are available in a data form which simplifies the further processing by different vehicle systems. For example, the detected information items can be made available to a driver assistance system.
Preferably there is provision that the validity of the at least one object and/or of the at least one object attribute is characterized as having been checked as soon as the threshold value of the object detection algorithm and/or of the object attribute detection algorithm is reached. Since the sensor raw data of the individual sensors or of the sensor group is, in any case, searched through for the objects or object attributes described by the first information item, and the said objects or object attributes are also detected when the threshold value is reached, information redundancy is therefore present when the threshold value is reached. A separate validity-checking process can therefore be dispensed with.
In a further preferred embodiment there is provision that the method is incorporated into a continuous sensor data fusion process, wherein each individual sensor makes available a separate second information item in each measurement cycle, or the sensor group makes available a multiplicity of second information items in each measurement cycle, wherein the sensor data fusion process compares objects and/or object attributes detected in the sensor raw data of the second information items with one another and/or supplements them and generates a common fusion information item in an evaluated data form, wherein the incorporation into the sensor data fusion process is carried out in such a way that objects and/or object attributes which are described in the first information item are compared and/or supplemented with the objects and object attributes detected in the sensor raw data of the second information items. This provides the advantage that an information profile, which is as complete as possible, of the vehicle surroundings can be generated in an individual fusion information item. A further advantage is that the fusion information item is present in an evaluated data form. This simplifies the further processing of the detected objects or object attributes by the different vehicle devices and driver assistance systems.
There is expediently provision that the at least one object whose validity is characterized as having been checked and/or the at least one object attribute whose validity is characterized as having been checked is made available in an evaluated data form to at least one driver assistance system, wherein the at least one driver assistance system is designed to warn a driver and/or to intervene in the vehicle control and/or to override a driver's prescription. The objects or object attributes whose validity is characterized as having been checked constitute reliable bases for the outputting of a warning to the driver or even for autonomous interventions in the vehicle control. As a result, incorrect warnings are avoided and a hazardous situation or a traffic accident can be averted, under certain circumstances even without the involvement of the driver.
The invention also relates to a system for accelerated object detection and for accelerated object attribute detection. The system comprises a vehicle-to-X communication device for acquiring a first information item, wherein the first information item describes at least one object and/or at least one object attribute in an evaluated data form, and at least one individual sensor or a sensor group for acquiring a second information item, wherein the second information item describes at least one object and/or at least one object attribute in a sensor raw data form.
Furthermore, the system comprises an analysis device, which is coupled at a data level to the vehicle-to-X communication device and to the at least one individual sensor or the sensor group and implements an object detection algorithm and/or an object attribute detection algorithm and applies it to sensor raw data of the second information item. The system according to the invention is defined by the fact that the analysis device reduces a threshold value of the object detection algorithm and/or object attribute detection algorithm in order to detect the at least one object described by the first information item and/or at least one object attribute in the sensor raw data of the second information item. The system according to the invention therefore comprises all the necessary means for carrying out the method according to the invention, and easily permits accelerated object detection or object attribute detection in the sensor raw data of the individual sensor or of the sensor group. This results in the advantages already described.
The system is preferably defined by the fact that the analysis device comprises an electronic computational unit which carries out at least some of the computational operations for vehicle devices which are different from the analysis device. This provides the advantage that not every vehicle device has to be provided with a separate computational unit, which both simplifies the manufacturing process and reduces the production costs. The computational unit which is included in the analysis device can be structurally assigned either to the analysis device itself or else to a vehicle device which is different from the analysis device. The fact that different vehicle devices jointly access the same computational unit also results in an effective and rapid combination of data of the corresponding vehicle devices.
Furthermore, it is advantageous that when the threshold value is reached, the analysis device converts a description of the at least one detected object and/or the at least one detected object attribute from a sensor raw data form into an evaluated data form. This simplifies the further processing of the reliably detected information items.
Preferably there is provision that the analysis device additionally carries out a continuous sensor data fusion process, wherein each individual sensor makes available a separate second information item in each measurement cycle, or the sensor group makes available a multiplicity of second information items in each measurement cycle, wherein the sensor data fusion process compares objects and/or object attributes detected in the sensor raw data of the second information items with one another and/or supplements them and generates a common fusion information item in an evaluated data form, wherein the analysis device compares and/or supplements objects and/or object attributes described in the first information item with the objects and/or object attributes detected in the sensor raw data of the second information items. This generates an information profile of the vehicle surroundings which is as complete as possible, in just a single fusion information item. Since the fusion information item is additionally present in an evaluated data form, the further processing by corresponding driver assistance systems and vehicle devices is simplified.
Preferably there is provision that the at least one individual sensor or the sensor group acquires the second information item on the basis of at least one of the following operational principles:
lidar,
radar,
a camera, and
ultrasonic sound.
These are sensor types which are typically used in the field of motor vehicles and essentially permit comprehensive sensing and detection of the vehicle surroundings. At the present time, a large number of vehicles are already equipped with a plurality of sensors of the specified types on a standard basis, and this number will increase further in future. The additional equipment expenditure for implementing the method according to the invention in a motor vehicle is therefore low.
It is advantageous that the vehicle-to-X communication device acquires the first information item on the basis of at least one of the following types of connection:
WLAN connection, in particular according to IEEE 802.11,
ISM connection (Industrial, Scientific, Medical Band),
Bluetooth,
ZigBee,
UWB,
WiMax,
infrared link, and
mobile radio link.
These types of connection provide different advantages and disadvantages here, depending on the type and wavelength. WLAN connections permit, for example, a high data transmission rate and a rapid connection setup. In contrast, ISM connections provide only a relatively low data transmission rate, but are outstandingly suitable for transmitting data around obstructions. Infrared links again also provide a low data transmission rate. Finally, mobile radio links are not adversely affected by obstructions and provide a good data transmission rate. However, the connection setup is comparatively slow for these. Further advantages are obtained by combining and using a plurality of these types of connections simultaneously or in parallel, since in this way the disadvantages of individual types of connection can be compensated.
Furthermore, the present invention relates to a use of the method for accelerated object detection and/or for accelerated object attribute detection in a motor vehicle.